The effects of supplementing grazing dairy cows with partial mixed ration on enteric methane emissions and milk production during mid to late lactation.

This study compared the enteric CH(4) emissions and milk production of cows offered various grass-based diets during mid to late lactation. Forty-eight spring-calving Holstein-Friesian dairy cows were randomly assigned to 1 of 3 nutritional treatments for 8 wk: (1) low grass allowance (LGA) + partial mixed ration (PMR), (2) high grass allowance (HGA), or (3) LGA. The PMR group received an allocation of 13.9 kg of grass dry matter (DM)/cow per day and in addition were offered 4.1 kg of PMR DM/cow per day. The HGA group received an allocation of 19.3 kg of grass DM/cow per day and the LGA group received an allocation of 14.4 kg of grass DM/cow per day. The PMR offered was composed of 450 g of maize silage/kg of DM, 450 g of concentrate blend/kg of DM, and 100g of barley straw/kg of DM. Daily CH(4) emissions were determined using the emissions from ruminants using a calibrated tracer technique, using sulfur hexafluoride, for 5 consecutive days during 2 periods. Simultaneously, grass DM intake (DMI) was estimated using the n-alkane technique and the PMR DMI was also recorded. Cows offered PMR had higher DMI than either the HGA or LGA cows (16.5 vs. 14.9 and 13.9 kg of DM/d). The higher DMI of PMR cows increased milk production relative to HGA and LGA cows: milk yield (17.0 vs. 14.6 and 13.1 kg) and fat and protein yield (1.29 vs. 1.14 and 1.04 kg). Daily CH(4) emissions were higher for the PMR group than for the HGA and LGA groups (406 vs. 384 and 349 g/cow per day). The enteric CH(4) emissions intensity per unit of DMI, milk yield, solids-corrected milk yield, and fat and protein yield did not differ between treatments. Effects observed in the PMR treatment were due to an increase in DMI rather than to any nutritional characteristic of the PMR.

Effects of a perennial ryegrass diet or total mixed ration diet offered to spring-calving Holstein-Friesian dairy cows on methane emissions, dry matter intake, and milk production.

The objective of the present study was to compare the enteric methane (CH4) emissions and milk production of spring-calving Holstein-Friesian cows offered either a grazed perennial ryegrass diet or a total mixed ration (TMR) diet for 10 wk in early lactation. Forty-eight spring-calving Holstein-Friesian dairy cows were randomly assigned to 1 of 2 nutritional treatments for 10 wk: 1) grass or 2) TMR. The grass group received an allocation of 17 kg of dry matter (DM) of grass per cow per day with a pre-grazing herbage mass of 1,492 kg of DM/ha. The TMR offered per cow per day was composed of maize silage (7.5 kg of DM), concentrate blend (8.6 kg of DM), grass silage (3.5 kg of DM), molasses (0.7 kg of DM), and straw (0.5 kg of DM). Daily CH4 emissions were determined via the emissions from ruminants using a calibrated tracer technique for 5 consecutive days during wk 4 and 10 of the study. Simultaneously, herbage dry matter intake (DMI) for the grass group was estimated using the n-alkane technique, whereas DMI for the TMR group was recorded using the Griffith Elder feeding system. Cows offered TMR had higher milk yield (29.5 vs. 21.1 kg/d), solids-corrected milk yield (27.7 vs. 20.1 kg/d), fat and protein (FP) yield (2.09 vs. 1.54 kg/d), bodyweight change (0.54 kg of gain/d vs. 0.37 kg of loss/d), and body condition score change (0.36 unit gain vs. 0.33 unit loss) than did the grass group over the course of the 10-wk study. Methane emissions were higher for the TMR group than the grass group (397 vs. 251 g/cow per day). The TMR group also emitted more CH4 per kg of FP (200 vs. 174 g/kg of FP) than did the grass group. They also emitted more CH4 per kg of DMI (20.28 vs. 18.06 g/kg of DMI) than did the grass group. In this study, spring-calving cows, consuming a high quality perennial ryegrass diet in the spring, produced less enteric CH4 emissions per cow, per unit of intake, and per unit of FP than did cows offered a standard TMR diet.

Effect of pregrazing herbage mass on methane production, dry matter intake, and milk production of grazing dairy cows during the mid-season period.

Increasing milk production from pasture while increasing grass dry matter intake (GDMI) and lowering methane (CH(4)) emissions are key objectives of low-cost dairy production systems. It was hypothesized that offering swards of low herbage mass with increased digestibility leads to increased milk output. A grazing experiment was undertaken to investigate the effects of varying levels of HM on CH(4) emissions, GDMI and milk production of grazing dairy cows during the mid-season grazing period (June to July). Prior to the experiment, 46 Holstein-Friesian dairy cows (46 d in milk) were randomly assigned to 1 of 2 treatments (n=23) in a randomized block design. The 2 treatments consisted of 2 target pregrazing HM: 1,000 kg of dry matter (DM)/ha (low herbage mass, LHM) or 2,200 kg of DM/ha (high herbage mass, HHM). The experimental period lasted 2 mo from June 1 until July 31. Within the experimental period, there were 2 measurement periods, measurement 1 (M1) and measurement 2 (M2), where CH(4) emissions, GDMI, and milk production were measured. Mean herbage mass throughout the measurement periods was 1,075 kg of DM/ha and 1,993 kg of DM/ha for the LHM and HHM treatments, respectively. Grass quality in terms of organic matter digestibility was significantly higher for the LHM treatment in M2 (+12 g/kg of DM). In M1, the effect of herbage mass on grass quality was approaching significance in favor of the LHM treatment. Herbage mass did not significantly affect milk production during the measurement periods. Cows grazing the LHM swards had increased GDMI in M1 (+1.5 kg of DM) compared with cows grazing the HHM swards; no difference in GDMI was observed in M2. Grazing HHM swards increased CH(4) production per cow per day (+42 g), per kilogram of milk yield (+3.5 g/kg of milk), per kilogram of milk solids (+47 g/kg of milk solids), and per kilogram of GDMI (+3.1 g/kg of GDMI) in M2. Cows grazing the HHM swards lost a greater proportion of their gross energy intake as CH(4) during both measurement periods (+0.9% and +1% for M1 and M2, respectively). It was concluded that grazing LHM swards would increase grass quality with a concurrent reduction in CH(4) emissions.

Non-detection of Chlamydia species in carotid atheroma using generic primers by nested PCR in a population with a high prevalence of Chlamydia pneumoniae antibody.

BACKGROUND: The association of Chlamydia pneumoniae with atherosclerosis is controversial. We investigated the presence of C. pneumoniae and other Chlamydia spp. in atheromatous carotid artery tissue. METHODS: Forty elective carotid endarterectomy patients were recruited (27 males, mean age 65 and 13 females mean age 68), 4 had bilateral carotid endarterectomies (n= 44 endarterectomy specimens). Control specimens were taken from macroscopically normal carotid artery adjacent to the atheromatous lesions (internal controls), except in 8 cases where normal carotid arteries from post mortem (external controls) were used. Three case-control pairs were excluded when the HLA DRB gene failed to amplify from the DNA. Genus specific primers to the major outer membrane protein (MOMP) gene were used in a nested polymerase chain reaction (nPCR) in 41 atheromatous carotid specimens and paired controls. PCR inhibition was monitored by spiking with target C. trachomatis. Atheroma severity was graded histologically. Plasma samples were tested by microimmunofluorescence (MIF) for antibodies to C. pneumoniae, C. trachomatis and C. psittaci and the corresponding white cells were tested for Chlamydia spp. by nPCR. RESULTS: C. pneumoniae was not detected in any carotid specimen. Twenty-five of 38 (66%) plasma specimens were positive for C. pneumoniae IgG, 2/38 (5%) for C. trachomatis IgG and 1/38 (3%) for C. psittaci IgG. CONCLUSIONS: We were unable to show an association between the presence of Chlamydia spp. and atheroma in carotid arteries in the presence of a high seroprevalence of C. pneumoniae antibodies in Northern Ireland.

Testicular torsion: time is the enemy.

BACKGROUND: The acute scrotum is a diagnostic dilemma, and testicular torsion is of primary interest because of its fertility problems for the patient and medico-legal issues for the surgeon. The present study aimed to correlate operative findings of patients with suspected testicular torsion with certain clinical variables and investigations to see if diagnosis and outcome could be improved. METHODS: A total of 99 patients underwent scrotal exploration for suspected testicular torsion at the Royal Brisbane Hospital between 1990 and 1995. Colour Doppler ultrasound, white blood count and urine microscopy results were documented, along with the patient's age and duration of testicular pain. RESULTS: Fifty-six patients were found to have torsion, and the testicular loss rate was 23%. Patients who experienced testicular pain for longer than 12 h had a testicular loss rate of 67%. A negative urine microscopy was suggestive of testicular torsion, but was not diagnostic. The white blood count did not aid in the diagnosis. Colour Doppler ultrasound of the scrotum was used on nine occasions with three false negative results and a sensitivity of only 57%. CONCLUSIONS: Time is the enemy when managing the acute scrotum. No investigation substantially improves clinical diagnosis enough to warrant any delay in definitive surgical intervention.

Nested primers improve sensitivity in the detection of Helicobacter pylori by the polymerase chain reaction.

To investigate potential routes of spread of infection by the polymerase chain reaction (PCR) it is important that the technique is effective in the types of specimen to be investigated. To establish the limits of detection of Helicobacter pylori by PCR in clinical material from the gastric mucosa, faeces, dental plaque and oral rinses, samples were seeded with known numbers of bacteria. DNA extraction was followed by amplification with primers from the urease C gene. Nested primers were used to amplify the PCR product which was detected using a digoxigenin-labelled probe. Faeces or plaque inhibited the single reaction 10(2)-10(6) fold. A second amplification using nested primers and probing increased the sensitivity to a level similar to that obtained with pure culture. This method is potentially useful with less likelihood of false negative results when trying to detect H. pylori by PCR in highly contaminated, clinical material.

Intravascular fasciitis: a case report and review of the literature.

A 49 year old man presented with a mass in the inguinal region that for 3 mths had been associated with slight discomfort. Clinically the mass was thought to be an enlarged lymph node. Histology however showed nodular fasciitis. There was also an associated smaller lesion that was histologically identical and which involved the wall of a medium sized vein with protrusion into its lumen. These appearances were typical of intravascular fasciitis. Review of the Royal Brisbane Hospital Pathology files for 12 yrs from 1982, revealed no other such cases. We describe here the clinical and pathological features of this case and review the literature on this rare condition.

A comparison of the psychosocial aspects of AIDS and cancer-related bereavement.

OBJECTIVE: This study compares the psychological symptoms and bereavement distress of individuals bereaved by AIDS with a group bereaved by a cancer death, and addresses the question of whether an AIDS death is associated with a higher rate of adverse psychosocial factors that may increase risk of psychological morbidity in the bereaved individuals. METHOD: AIDS (n = 28) and cancer (n = 30) bereaved individuals (all within 3 months of the bereavement) completed measures of psychological morbidity and measures addressing a range of other adverse factors, e.g., number of losses, levels of social support and stigma. RESULTS: The cancer and AIDS bereaved were essentially similar on all psychological symptom measures. The AIDS group reported lower levels of social support in response to the bereavement than cancer bereaved individuals; a greater number of bereavements, were more likely to conceal the cause of death from significant others including their own family and perceived, in some instances, a greater level of rejection from others. The AIDS group reported higher levels of social support from friends than from family. CONCLUSIONS: At three months following bereavement, AIDS and cancer bereaved were similar in levels of distress. While this may change with the progress of grief over time, it suggests essentially similar early bereavement responses. Those bereaved by AIDS reported a range of other adverse factors such as a greater number of losses, lower social support, stigma, and less open disclosure of the cause of death.

Nodular fasciitis and related pseudosarcomatous lesions of soft tissues.

BACKGROUND: Nodular fasciitis is characterized by a proliferation of spindle cells which may be misdiagnosed as sarcomas due to the rich cellularity, mitotic activity and variant morphologic patterns. METHODS: This report includes 42 cases of nodular fasciitis and related conditions of skin and soft tissue from the pathology files of the Royal Brisbane Hospital, Queensland, Australia. There were 33 cases of nodular fasciitis, three cases of ossifying fasciitis, three cases of proliferative fasciitis, two cases of proliferative myositis and one case of intravascular fasciitis. Two-thirds of cases were referred from outside Royal Brisbane Hospital. RESULTS: Nodular fasciitis and ossifying occurred most commonly in young adults with 16 patients (44%) between the ages of 20 and 29. However, the other variants of nodular fasciitis including proliferative myositis and intravascular fasciitis occurred in older people (six patients being older than 49 years) and more commonly occurring in men (n=5). A painless rapidly growing mass was most common. The lesions of nodular fasciitis were most often located in the upper extremity with the forearm most commonly affected. CONCLUSIONS: Nodular fasciitis and related conditions are benign. All patients are alive and well 3 months to 13 years (mean 7.2 years) after simple local resection.

Modulatory action of Helicobacter pylori on histamine release from mast cells and basophils in vitro.

Helicobacter pylori is important in the aetiology of peptic ulceration. Despite inducing an inflammatory response in the mucosa, the organism persists, suggesting that it has efficient protective mechanisms. Some bacterial and viral products modulate histamine secretion from inflammatory cells. Therefore, this study examined the modulatory effects of H. pylori preparations on histamine release from rat peritoneal mast cells and human basophils. Eleven clinical isolates of H. pylori were prepared in different ways: as whole washed bacteria, washed sonicated bacteria, and formalin-killed bacteria, and as outermembrane and lipopolysaccharide (LPS) extracts. Histamine release from mast cells or basophils was not elicited by any of these bacterial preparations alone. However, when mixed with various secretory stimulants, the bacterial preparations caused inhibition of histamine release from rat mast cells (calcium ionophore A23187, compound 48/80, concanavalin A, anti-rat IgE) and human basophils (A23187, N-formyl Met-Leu-Phe). The degree of inhibition ranged from 48% to 97%. These results indicate that H. pylori exerts an inhibitory effect on cells of the immune system that contributes to its persistence within the gastric mucosa.

Necrotizing pancreatitis: operating for life.

Infected necrotizing pancreatitis is the most fulminant variety of this disease. Colonic involvement and retroperitoneal fasciitis are particularly lethal. The reported mortality is up to 50%. The purpose of this study is to review our combined experience at the Princess Alexandra Hospital and the Royal Brisbane Hospital, Brisbane, to determine whether patient survival was related to a particular etiology, treatment, or complication. All patients treated since 1986 with infected pancreatitis who required surgical necrosectomy and then ventilation in the intensive care unit (ICU) were studied. There were 48 patients so managed. The median age of survivors was 52 years, and for those who died it was 64 years (p = 0.001). The etiology was gallstones in 22 and alcoholism in 12. Of the alcoholics, 11 survived and 1 died. Of the patients with gallstones, 13 survived and 9 died. There was an overall mortality of 31%. Survivors were in hospital for a median of 73 days, whereas deaths occurred after a median of 35 days (p = 0.04). Seven patients underwent hemofiltration; five survived, and two died. N-Acetylcysteine has been used in four patients, of whom three survived and one died. The abdomen was left open in 38 patients and kept closed in 10. Although Ranson's criteria at admission to the ICU did not predict survival, it was found that the median APACHE II score in survivors was significantly lower than in those who died (p = 0.025).(ABSTRACT TRUNCATED AT 250 WORDS)

Cell death and neuronal recruitment in the high vocal center of adult male canaries are temporally related to changes in song.

Adult male canaries modify their song every year. Most of these changes occur during late summer and early fall, after the end of the breeding season, and in late winter, immediately before the onset of the next breeding season. The high vocal center (HVC) is an important nucleus in the brain pathway that controls this learned behavior. New neurons continue to be added to the HVC of adult male canaries, where they replace older neurons that have died. The present report describes the monthly incidence of cell death and neuronal addition in the HVC of such birds. Different groups of 1- to 2-year-old male canaries were treated with [3H]thymidine, a marker of cell birth, during each month of the year and killed 27 days later. The ratio of 3H-labeled neurons to all neurons in the HVC showed seasonal peaks and troughs. This ratio was highest in October and March. Peaks in the ratio of pycnotic (dying) HVC cells to all neurons in HVC preceded the peaks in the ratio of 3H-labeled neurons. We suggest that seasonal peaks in cell loss and neuronal recruitment in HVC are related to endocrine changes and that all three play a role in the seasonality of song modification.

The life span of new neurons in a song control nucleus of the adult canary brain depends on time of year when these cells are born.

The number of high vocal center (HVC) neurons labeled in adult male canaries by systemic injections of [3H]thymidine depended on season and survival time. This was true for HVC neurons projecting to the robust nucleus of the archistriatum and for other HVC neurons that could not be retrogradely filled from the robust nucleus of the archistriatum. Birds injected in October and killed 40 days later had twice as many labeled HVC neurons as birds injected in May and killed 40 days later. However, this difference became much larger (5 times) when the birds were allowed to survive for 4 months. Whereas more than half of the spring-born neurons disappeared between 40 days and 4 months, there was no reduction in the number of fall-born neurons present at the 4-month survival point. We infer that seasonal variables affect the life span of HVC neurons born in adulthood.

Diagnosis of ruptured diaphragm following blunt trauma: results from 85 cases.

Between 1975 and 1990, 85 patients with diaphragmatic rupture following blunt trauma were treated at the Royal Brisbane and Princess Alexandra Hospitals, Brisbane. There were 65 on the left, 17 on the right and three were bilateral. Road trauma was the cause in 88% of cases. In the first 48 h the diagnosis was made by chest X-ray in 51 patients, laparotomy in 22, autopsy in two, emergency room thoracotomy, ultrasound and pneumoperitoneum each in a single patient. Seven patients (8%) had delay in diagnosis greater than 48 h ranging from 6 days to 6 months. Diagnosis was subsequently made by pneumoperitoneum (3), chest X-ray (1) and exploratory thoracotomy (1). Two patients presented with a strangulated diaphragmatic hernia 3 and 6 months following an acute admission with blunt chest trauma and urological trauma respectively. During the study period a further five patients presented with an obstructing diaphragmatic hernia. Sixteen patients died (19%), fifteen from associated injuries and one related to the diaphragmatic repair. Ruptured diaphragm should be suspected in patients with severe chest trauma, particularly those requiring positive pressure ventilation, patients with intra-abdominal injuries and those with pelvic fractures. Early recognition and repair results in low morbidity and mortality. Measures that confirmed the diagnosis in patients with delay included repeated chest X-rays and pneumoperitoneum.

On variables that affect estimates of the true sizes and densities of radioactively labeled cell nuclei.

Tritiated thymidine has been widely used as a nuclear marker of cell birth. The true diameters and packing densities (nuclei/microns 3) of such radioactively labeled nuclei cannot be measured directly from tissue sections. Here we show that existing stereological corrections cannot be applied to data from radioactively labeled nuclei. We empirically measured the number of silver grains exposed by nuclei containing tritiated thymidine. The nuclei were separated from the photographic emulsion by known thicknesses of fixed, embedded avian telencephalon. The results of this experiment were used to develop an equation that estimates the number of silver grains exposed by a cell nucleus of any given diameter, containing a given amount of radioactive label, and located at any given distance from the photographic emulsion. The equation also allows one to calculate the probability that a label-containing nucleus will be correctly classified as labeled. Simulations of the equation revealed that not all label-containing nuclei are correctly classified by using commonly employed identification procedures and that larger nuclei are less likely to be correctly classified than smaller nuclei, given the same amount of label. The equation can be used to modify one class of existing stereological equations so as to be applicable to measurements of radioactively labeled nuclei. Finally, we discuss the assumptions and limitations of this modification.

Cells born in adult canary forebrain are local interneurons.

Thymidine autoradiography and retrograde transport of horseradish peroxidase (HRP) were combined to determine the connectivity of neurons born in adult canary forebrain. Adult male and female canaries were pretreated with [3H]thymidine to label cells undergoing DNA synthesis prior to mitosis. Thirty or 60 days later, neurons in a forebrain nucleus, hyperstriatium ventralis, pars caudalis (HVc), were labeled by retrograde transport of HRP injected into the only two nuclei known to receive a projection from HVc: robustus archistriatalis (RA) and area X of lobus parolfactorius. The birds were then killed and brain sections were treated to visualize cells containing HRP; these sections were processed for autoradiography to detect [3H]thymidine-labeled cells in the same tissue. More than 9% of all neurons in HVc were thymidine labeled; but of the almost 20,000 HRP-labeled projection neurons examined, fewer than 20 (0.1%) were labeled by the thymidine treatment. Furthermore, the median cell body size for area X-projecting cells was significantly larger than that of thymidine-labeled cells, and the median size of thymidine-labeled cells was significantly larger than that of RA-projecting cells. The simplest interpretation of these results is that the new neurons incorporated into nucleus HVc in adult canary brain are local interneurons, intermediate in size between neurons projecting to RA and area X.

Human orientation with restricted sensory information: no evidence for magnetic sensitivity.

Baker claimed that people are also able to orientate themselves to particular geographical locations as a result of sensitivity to the Earth's magnetic field. These claims were disputed by Gould and Able. A study involving a greater number of subjects (n = 103) and more stringent control over environmental sensory cues was carried out to resolve this disagreement. Subjects responded, both with a direct pointing response and with a verbal judgement in terms of an imagined clock face, to the targets of north, home, and the City of Melbourne. In statistical terms, subjects were not able to orientate towards any target by use of either response. No evidence was found for a magnetic sense in humans as claimed by Baker.